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A263029 Numbers n such that A002322(n) + 1 is not a prime, where A002322 is Carmichael lambda. 5
25, 32, 50, 55, 75, 81, 96, 100, 110, 115, 119, 121, 128, 150, 153, 160, 162, 165, 176, 187, 200, 203, 209, 215, 220, 221, 224, 230, 235, 238, 242, 245, 253, 256, 261, 275, 287, 288, 289, 295, 297, 299, 300, 306, 319, 323, 324, 330, 335, 343, 345, 355 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A263028.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..25794

MATHEMATICA

Select[Range[1, 400], ! PrimeQ[CarmichaelLambda[#] + 1] &]

PROG

(MAGMA) [n: n in [2..400] | not IsPrime(CarmichaelLambda(n)+1)];

(PARI) for(n=1, 1e3, if(isprime((1 + lcm(znstar(n)[2]))) == 0, print1(n", "))) \\ Altug Alkan, Oct 12 2015

CROSSREFS

Cf. A002322, A263027, A263028.

Positions of zeros in A296077.

Cf. also A039689.

Sequence in context: A172007 A107258 A258876 * A225418 A035140 A050694

Adjacent sequences:  A263026 A263027 A263028 * A263030 A263031 A263032

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Oct 12 2015

STATUS

approved

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Last modified October 15 05:43 EDT 2019. Contains 328026 sequences. (Running on oeis4.)